The present invention relates to a channel housing used in channel systems comprising channels curving in plural branches, and to a manufacturing method therefor.
In general, any kind of complex channel system will require channels curving in plural branches. Assembly becomes accordingly complicated, the system more susceptible to breakdowns, and the volume of the housing holding the piping larger, making it impossible to achieve a compact channel system.
For example, engines using a so-called "sequential twin turbo system" are used as a means of providing high performance automotive engines. Normally, a map describing the operating range for the secondary turbocharger is provided as a function of the throttle opening and engine speed, and turbocharging is switched according to this map. As a result, the control solenoids and other aspects of the channels become complex and extremely varied, making installation in the confines of the engine room difficult, and increasing both weight and cost.
The negative pressure piping check valve used in channel systems used for engine control as described above has been previously proposed in Japanese Patent Jikkaisho No. 14071/1988. However, this does not provide a means for making the overall channel system more compact.
It therefore remains necessary to construct the overall channel system as compactly and light weight as possible when it is necessary to assemble a complex and varied channel system or similar assembly providing the control described above in an engine room or similarly confined space. Resolving this problem will also address various correlated concerns, including making assembly easier, and improving the reliability of the channel system.
Therefore, the first object of the present invention is to provide a housing comprising curving channels whereby complex and varied channels can be included compactly.
A further object of the invention is to provide a method for manufacturing a housing comprising curving channels by forming a plurality of mutually opposing partitions for forming said curving channels on the insides of a pair of molded bodies, and then bonding said partitions together. There are cases, however, when simply welding or bonding the bonding edges of the partitions is not sufficient to obtain adhesion strength exceeding a certain level.
Currently, methods for bonding a pair of molded bodies to form a hollow body have been proposed in Japanese patents Tokkaisho Nos. 63-237917 (1988) and 63-23918 (1988); Tokkaihei No. 2-20410 (1990); and Tokkouhei No. 2-38377 (1990). Each of these methods, however, involves bonding only the outside circumference of the molded body pair, and is not suited to bonding partitions for forming curving channels formed on the inside of molded bodies, as is necessary in a housing comprising curving channels.
Therefore, the second object of the present invention is to provide a method for manufacturing a housing comprising curving channels wherein strong bonds are formed between inside members.